| // Copyright 2024 The Dawn & Tint Authors |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are met: |
| // |
| // 1. Redistributions of source code must retain the above copyright notice, this |
| // list of conditions and the following disclaimer. |
| // |
| // 2. Redistributions in binary form must reproduce the above copyright notice, |
| // this list of conditions and the following disclaimer in the documentation |
| // and/or other materials provided with the distribution. |
| // |
| // 3. Neither the name of the copyright holder nor the names of its |
| // contributors may be used to endorse or promote products derived from |
| // this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE |
| // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
| // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| #include "src/tint/lang/hlsl/writer/raise/shader_io.h" |
| |
| #include <algorithm> |
| #include <memory> |
| #include <utility> |
| |
| #include "src/tint/lang/core/ir/builder.h" |
| #include "src/tint/lang/core/ir/module.h" |
| #include "src/tint/lang/core/ir/transform/shader_io.h" |
| #include "src/tint/lang/core/ir/validator.h" |
| #include "src/tint/lang/hlsl/builtin_fn.h" |
| #include "src/tint/lang/hlsl/ir/builtin_call.h" |
| |
| using namespace tint::core::fluent_types; // NOLINT |
| using namespace tint::core::number_suffixes; // NOLINT |
| |
| namespace tint::hlsl::writer::raise { |
| |
| namespace { |
| |
| /// PIMPL state for the parts of the shader IO transform specific to HLSL. |
| /// For HLSL, move all inputs to a struct passed as an entry point parameter, and wrap outputs in |
| /// a structure returned by the entry point. |
| struct StateImpl : core::ir::transform::ShaderIOBackendState { |
| /// The config |
| const ShaderIOConfig& config; |
| |
| /// The input parameter |
| core::ir::FunctionParam* input_param = nullptr; |
| |
| Vector<uint32_t, 4> input_indices; |
| Vector<uint32_t, 4> output_indices; |
| |
| /// The output struct type. |
| core::type::Struct* output_struct = nullptr; |
| |
| /// The output values to return from the entry point. |
| Vector<core::ir::Value*, 4> output_values; |
| |
| // Indices of inputs that require special handling |
| std::optional<uint32_t> subgroup_invocation_id_index; |
| std::optional<uint32_t> subgroup_size_index; |
| std::optional<uint32_t> num_workgroups_index; |
| |
| /// Constructor |
| StateImpl(core::ir::Module& mod, core::ir::Function* f, const ShaderIOConfig& c) |
| : ShaderIOBackendState(mod, f), config(c) {} |
| |
| /// Destructor |
| ~StateImpl() override {} |
| |
| /// FXC is sensitive to field order in structures, this is used by StructMemberComparator to |
| /// ensure that FXC is happy with the order of emitted fields. |
| uint32_t BuiltinOrder(core::BuiltinValue builtin) { |
| switch (builtin) { |
| case core::BuiltinValue::kPosition: |
| return 1; |
| case core::BuiltinValue::kVertexIndex: |
| return 2; |
| case core::BuiltinValue::kInstanceIndex: |
| return 3; |
| case core::BuiltinValue::kFrontFacing: |
| return 4; |
| case core::BuiltinValue::kFragDepth: |
| return 5; |
| case core::BuiltinValue::kLocalInvocationId: |
| return 6; |
| case core::BuiltinValue::kLocalInvocationIndex: |
| return 7; |
| case core::BuiltinValue::kGlobalInvocationId: |
| return 8; |
| case core::BuiltinValue::kWorkgroupId: |
| return 9; |
| case core::BuiltinValue::kNumWorkgroups: |
| return 10; |
| case core::BuiltinValue::kSampleIndex: |
| return 11; |
| case core::BuiltinValue::kSampleMask: |
| return 12; |
| case core::BuiltinValue::kPointSize: |
| return 13; |
| default: |
| break; |
| } |
| TINT_UNREACHABLE() << "Unhandled builtin value: " << ToString(builtin); |
| } |
| |
| struct MemberInfo { |
| core::type::Manager::StructMemberDesc member; |
| uint32_t idx; |
| }; |
| |
| /// Comparison function used to reorder struct members such that all members with |
| /// color attributes appear first (ordered by color slot), then location attributes (ordered by |
| /// location slot), then blend_src attributes (ordered by blend_src slot), followed by those |
| /// with builtin attributes (ordered by BuiltinOrder). |
| /// @param x a struct member |
| /// @param y another struct member |
| /// @returns true if a comes before b |
| bool StructMemberComparator(const MemberInfo& x, const MemberInfo& y) { |
| if (x.member.attributes.color.has_value() && y.member.attributes.color.has_value() && |
| x.member.attributes.color != y.member.attributes.color) { |
| // Both have color attributes: smallest goes first. |
| return x.member.attributes.color < y.member.attributes.color; |
| } else if (x.member.attributes.color.has_value() != y.member.attributes.color.has_value()) { |
| // The member with the color goes first |
| return x.member.attributes.color.has_value(); |
| } |
| |
| if (x.member.attributes.location.has_value() && y.member.attributes.location.has_value() && |
| x.member.attributes.location != y.member.attributes.location) { |
| // Both have location attributes: smallest goes first. |
| return x.member.attributes.location < y.member.attributes.location; |
| } else if (x.member.attributes.location.has_value() != |
| y.member.attributes.location.has_value()) { |
| // The member with the location goes first |
| return x.member.attributes.location.has_value(); |
| } |
| |
| if (x.member.attributes.blend_src.has_value() && |
| y.member.attributes.blend_src.has_value() && |
| x.member.attributes.blend_src != y.member.attributes.blend_src) { |
| // Both have blend_src attributes: smallest goes first. |
| return x.member.attributes.blend_src < y.member.attributes.blend_src; |
| } else if (x.member.attributes.blend_src.has_value() != |
| y.member.attributes.blend_src.has_value()) { |
| // The member with the blend_src goes first |
| return x.member.attributes.blend_src.has_value(); |
| } |
| |
| auto x_blt = x.member.attributes.builtin; |
| auto y_blt = y.member.attributes.builtin; |
| if (x_blt.has_value() && y_blt.has_value()) { |
| // Both are builtins: order matters for FXC. |
| auto order_a = BuiltinOrder(*x_blt); |
| auto order_b = BuiltinOrder(*y_blt); |
| if (order_a != order_b) { |
| return order_a < order_b; |
| } |
| } else if (x_blt.has_value() != y_blt.has_value()) { |
| // The member with the builtin goes first |
| return x_blt.has_value(); |
| } |
| |
| // Control flow reaches here if x is the same as y. |
| // Sort algorithms sometimes do that. |
| return false; |
| } |
| |
| /// @copydoc ShaderIO::BackendState::FinalizeInputs |
| Vector<core::ir::FunctionParam*, 4> FinalizeInputs() override { |
| Vector<core::type::Manager::StructMemberDesc, 4> input_struct_members; |
| |
| Vector<MemberInfo, 4> input_data; |
| for (uint32_t i = 0; i < inputs.Length(); ++i) { |
| // If subgroup invocation id or size, save the index for GetInput |
| if (auto builtin = inputs[i].attributes.builtin) { |
| if (*builtin == core::BuiltinValue::kSubgroupInvocationId) { |
| subgroup_invocation_id_index = i; |
| continue; |
| } else if (*builtin == core::BuiltinValue::kSubgroupSize) { |
| subgroup_size_index = i; |
| continue; |
| } else if (*builtin == core::BuiltinValue::kNumWorkgroups) { |
| num_workgroups_index = i; |
| continue; |
| } |
| } |
| |
| input_data.Push(MemberInfo{inputs[i], i}); |
| } |
| |
| input_indices.Resize(input_data.Length()); |
| |
| // Sort the struct members to satisfy HLSL interfacing matching rules. |
| std::sort(input_data.begin(), input_data.end(), |
| [&](auto& x, auto& y) { return StructMemberComparator(x, y); }); |
| |
| for (auto& input : input_data) { |
| input_indices[input.idx] = static_cast<uint32_t>(input_struct_members.Length()); |
| input_struct_members.Push(input.member); |
| } |
| |
| if (!input_struct_members.IsEmpty()) { |
| auto* input_struct = ty.Struct(ir.symbols.New(ir.NameOf(func).Name() + "_inputs"), |
| std::move(input_struct_members)); |
| switch (func->Stage()) { |
| case core::ir::Function::PipelineStage::kFragment: |
| input_struct->AddUsage(core::type::PipelineStageUsage::kFragmentInput); |
| break; |
| case core::ir::Function::PipelineStage::kVertex: |
| input_struct->AddUsage(core::type::PipelineStageUsage::kVertexInput); |
| break; |
| case core::ir::Function::PipelineStage::kCompute: |
| input_struct->AddUsage(core::type::PipelineStageUsage::kComputeInput); |
| break; |
| case core::ir::Function::PipelineStage::kUndefined: |
| TINT_UNREACHABLE(); |
| } |
| input_param = b.FunctionParam("inputs", input_struct); |
| return {input_param}; |
| } |
| |
| return tint::Empty; |
| } |
| |
| /// @copydoc ShaderIO::BackendState::FinalizeOutputs |
| const core::type::Type* FinalizeOutputs() override { |
| if (outputs.IsEmpty()) { |
| return ty.void_(); |
| } |
| |
| Vector<MemberInfo, 4> output_data; |
| for (uint32_t i = 0; i < outputs.Length(); ++i) { |
| output_data.Push(MemberInfo{outputs[i], i}); |
| } |
| |
| // Sort the struct members to satisfy HLSL interfacing matching rules. |
| std::sort(output_data.begin(), output_data.end(), |
| [&](auto& x, auto& y) { return StructMemberComparator(x, y); }); |
| |
| output_indices.Resize(outputs.Length()); |
| output_values.Resize(outputs.Length()); |
| |
| Vector<core::type::Manager::StructMemberDesc, 4> output_struct_members; |
| for (size_t i = 0; i < output_data.Length(); ++i) { |
| output_indices[output_data[i].idx] = static_cast<uint32_t>(i); |
| output_struct_members.Push(output_data[i].member); |
| } |
| |
| output_struct = |
| ty.Struct(ir.symbols.New(ir.NameOf(func).Name() + "_outputs"), output_struct_members); |
| switch (func->Stage()) { |
| case core::ir::Function::PipelineStage::kFragment: |
| output_struct->AddUsage(core::type::PipelineStageUsage::kFragmentOutput); |
| break; |
| case core::ir::Function::PipelineStage::kVertex: |
| output_struct->AddUsage(core::type::PipelineStageUsage::kVertexOutput); |
| break; |
| case core::ir::Function::PipelineStage::kCompute: |
| output_struct->AddUsage(core::type::PipelineStageUsage::kComputeOutput); |
| break; |
| case core::ir::Function::PipelineStage::kUndefined: |
| TINT_UNREACHABLE(); |
| } |
| return output_struct; |
| } |
| |
| /// Handles kNumWorkgroups builtin by emitting a UBO to hold the num_workgroups value, |
| /// along with the load of the value. Returns the loaded value. |
| core::ir::Value* GetInputForNumWorkgroups(core::ir::Builder& builder) { |
| // Create uniform var that will receive the number of workgroups |
| core::ir::Var* num_wg_var = nullptr; |
| builder.Append(ir.root_block, [&] { |
| num_wg_var = builder.Var("tint_num_workgroups", ty.ptr(uniform, ty.vec3<u32>())); |
| }); |
| if (config.num_workgroups_binding.has_value()) { |
| // If config.num_workgroups_binding holds a value, use it. |
| auto bp = *config.num_workgroups_binding; |
| num_wg_var->SetBindingPoint(bp.group, bp.binding); |
| } else { |
| // Otherwise, use the binding 0 of the largest used group plus 1, or group 0 if no |
| // resources are bound. |
| uint32_t group = 0; |
| for (auto* inst : *ir.root_block.Get()) { |
| if (auto* var = inst->As<core::ir::Var>()) { |
| if (const auto& bp = var->BindingPoint()) { |
| if (bp->group >= group) { |
| group = bp->group + 1; |
| } |
| } |
| } |
| } |
| num_wg_var->SetBindingPoint(group, 0); |
| } |
| auto* load = builder.Load(num_wg_var); |
| return load->Result(0); |
| } |
| |
| /// @copydoc ShaderIO::BackendState::GetInput |
| core::ir::Value* GetInput(core::ir::Builder& builder, uint32_t idx) override { |
| if (subgroup_invocation_id_index == idx) { |
| return builder |
| .Call<hlsl::ir::BuiltinCall>(ty.u32(), hlsl::BuiltinFn::kWaveGetLaneIndex) |
| ->Result(0); |
| } |
| if (subgroup_size_index == idx) { |
| return builder |
| .Call<hlsl::ir::BuiltinCall>(ty.u32(), hlsl::BuiltinFn::kWaveGetLaneCount) |
| ->Result(0); |
| } |
| if (num_workgroups_index == idx) { |
| return GetInputForNumWorkgroups(builder); |
| } |
| |
| auto index = input_indices[idx]; |
| |
| core::ir::Value* v = builder.Access(inputs[idx].type, input_param, u32(index))->Result(0); |
| |
| // If this is an input position builtin we need to invert the 'w' component of the vector. |
| if (inputs[idx].attributes.builtin == core::BuiltinValue::kPosition) { |
| auto* w = builder.Access(ty.f32(), v, 3_u); |
| auto* div = builder.Divide(ty.f32(), 1.0_f, w); |
| auto* swizzle = builder.Swizzle(ty.vec3<f32>(), v, {0, 1, 2}); |
| v = builder.Construct(ty.vec4<f32>(), swizzle, div)->Results()[0]; |
| } |
| |
| return v; |
| } |
| |
| /// @copydoc ShaderIO::BackendState::SetOutput |
| void SetOutput(core::ir::Builder&, uint32_t idx, core::ir::Value* value) override { |
| auto index = output_indices[idx]; |
| output_values[index] = value; |
| } |
| |
| /// @copydoc ShaderIO::BackendState::MakeReturnValue |
| core::ir::Value* MakeReturnValue(core::ir::Builder& builder) override { |
| if (!output_struct) { |
| return nullptr; |
| } |
| return builder.Construct(output_struct, std::move(output_values))->Result(0); |
| } |
| }; |
| } // namespace |
| |
| Result<SuccessType> ShaderIO(core::ir::Module& ir, const ShaderIOConfig& config) { |
| auto result = ValidateAndDumpIfNeeded(ir, "ShaderIO transform"); |
| if (result != Success) { |
| return result; |
| } |
| |
| core::ir::transform::RunShaderIOBase(ir, [&](core::ir::Module& mod, core::ir::Function* func) { |
| return std::make_unique<StateImpl>(mod, func, config); |
| }); |
| |
| return Success; |
| } |
| |
| } // namespace tint::hlsl::writer::raise |
